The characters were designed by Peter Laird while they were negotiating the action figure deal with Playmates,[4][5] as they wanted more characters to release. They were added into the show and given names, personalities and an origin story by writer David Wise, based on instructions by Fred Wolf to "put more mutants in the series".[6]

Bebop (voiced by Barry Gordon in most appearances, Greg Berg in some 1989 episodes) and Rocksteady (voiced by Cam Clarke) were introduced in the series as part of a human street gang in New York City that was employed by Shredder. Rocksteady was a short and stocky blond Caucasian man (who sported army camouflage pants that would be replaced with simple beige cargo pants later while also occasionally sporting a strong Army helmet on his head in his mutated form). Bebop was a taller African American man with a purple Mohawk. With the other members of their gang, they were sent out to stop a Channel 6 reporter named April O'Neil from doing a report about crime in the city. April ran down into the sewers while being chased by the street gang and met the Teenage Mutant Ninja Turtles, who then defeated the gang in a fight.

After this humiliating setback, The Shredder developed a plan to defeat the Turtles by mutating members of the street gang that Rocksteady and Bebop are a part of so that they would have abilities greater than the Turtles'. Rocksteady and Bebop both volunteered to undergo the procedure (though neither was particularly aware of what it would entail) first with the promise that it would allow them to exact revenge on the Turtles. As the result of being brought into contact with a common warthog and a black rhinoceros that Shredder had abducted from the zoo, Bebop mutated into a humanoid mutant warthog while Rocksteady mutated into a humanoid mutant black rhinoceros.

Although the transformation did make them larger and stronger, they remained incompetent simpletons and were completely inept at stopping the Turtles or carrying out Shredder's plans. Throughout most of the series, they tried to attack the Turtles with brute force, without applying knowledge and strategy. In the episode "The Missing Map", when the two were accidentally caught in Krang's "brain extraction" machine, the results concluded there was "no data to extract", implying that the two possessed little or no knowledge. For most of the series they were employed for purposes however, the Turtles certainly consider them to be formidable (despite their stupidity) in combat due to their great strength and endurance, and as such, often use their intelligence to outwit them rather than fighting them in a straightforward manner. But their attempts at the turtles seem to regularly fail due to their incompetence and goofing behavior, which all leads to them being abused both physically and verbally by Shredder and Krang, and the former even fired them in one episode.

In one episode of the series, Bebop was shown to have kept a pet turtle, which got mutated into the evil turtle Slash.

In Planet of the Turtleoids, Part 1, Bebop and Rocksteady were responsible for causing a red cattle and a mole to be exposed to a mutagen-showering machine at the zoo transforming them into Groundchuck and Dirtbag at the time when Shredder and Krang wanted to mutate a lion and a gorilla (which were freed by the Turtleoid Kerma) to be their latest henchmen.

In season eight, Bebop along with Rocksteady seemed to have some form of intelligence, and talked and joked around less. Rocksteady and Bebop's last appearance is in the season 8 finale Turtle Trek. In that episode, the Turtles destroy the Technodrome's engines, trapping it and its inhabitants in Dimension X for good. While their bosses Krang and Shredder returned in the 10th and final season, Bebop and Rocksteady did not. Their whereabouts after being trapped in Dimension X were not explained.

They made a reappearance in the made-for-TV movie 'Turtles Forever'. In the flashback describing how the Turtles crossed dimensions, they said to their Turtle counterparts that they were facing off against Shredder and the Technodrome, meaning that he got the machine out of Dimension X (as well as Rocksteady and Bebop). Their incompetence is still shown, although it ended up saving the 2003 Shredder when Rocksteady accidentally tripped over and unplugged a laser that was about to destroy him, although Bebop ended up obliterating the 2003 Shredder anyway when he replugged the same laser device all the while thinking he would be pleased that they "fixed" his machine. All this happened just as the Utrom Shredder was unleashing a plan that would wipe out Ninja Turtles of all planes of existence (even if it meant destroying himself since he was still linked to them), so ironically...Bebop saved all of Turtle existence.

He first appeared in "Enemy of My Enemy," where he met with Shredder for a weapons deal. Shredder didn't seem to trust him very well, and had the cargo searched just in case Steranko was pulling any tricks. During the Turtles' fight with Shredder, Steranko got knocked out by the weapon that was being sold to the Foot Clan.

In "A Chinatown Ghost Story," it was mentioned that Steranko would pay the Purple Dragons through the roof for the Mystic Dagger.

Bebop was later on introduced as Anton Zeck, an African-American professional thief in a high-tech Tron-like suit with an energy Mohawk, his dance is almost similar to Michael Jackson's moves, and armed with high-tech gadgets who gave Steranko his diamond right eye in an earlier encounter.

He first appeared in "The Legend of the Kuro Kabuto," where he was sent by Steranko to steal Shredder's helmet, the titular Kuro Kabuto. Following his theft, where he left his calling card on a glued-down Rahzar, Zeck ran into the Turtles, who stole the kabuto from him. The Turtles, Rahzar, Fishface, Tiger Claw, and Baxter Stockman fought Zeck over the helmet, but he managed to evade them. When Zeck met up with Steranko in his helicopter, they both discovered that Leonardo swapped the helmet out with dirty diapers at the last minute, to Steranko's rage.

In "Serpent Hunt," several months after the Kraang conquered New York, Steranko and Zeck, desperate to escape their grasp, resolved to capture the mutated Karai in exchange for Shredder securing their safe departure from the city. The duo succeeded, but Shredder was livid at the revelation that Steranko was behind the theft of the Kabuto helmet, and a battle with the Turtles and the Foot Clan ensued over the captured Karai, who eventually escaped. Enraged, Shredder proceeded to have the duo mutated in Stockman-Fly's lab, despite Steranko's pleads for forgiveness. As the result of pouring warthog and white rhinoceros DNA into two mutagen batches, Zeck and Steranko mutated into a tall and thin humanoid mutant warthog with a short left tusk, heightened smell, superhuman strength, and the high tech parts of his suit fused onto his skin and an 8 ft. humanoid mutant white rhinoceros with a hook-lipped mouth, a jagged horn used as a sword or battering ram, superhuman strength and charging speed, and the tops of his knuckle dusters and shoulder pads (which end up assuming a different shape and growing a third spike on each) fused onto his skin that Michelangelo dubbed Bebop and Rocksteady.

In "The Pig and the Rhino," the two were forced to join the Foot Clan upon being beaten up by Shredder and tasked with once again retrieving Karai for Shredder. However, Bebop and Rocksteady decided to withdraw from the task for a while to get revenge of the Turtles, believing that if they hadn't interfered with the deal at the docks, they wouldn't be in their current condition. They subdued Donatello, Raphael, April O'Neil and Casey Jones and held them hostage. After they cornered the last two Turtles at Coney Island, Leonardo freed the hostages while Michelangelo distracted the captors by trying to come up with mutant names, finally getting them off of the van that they arrived in. While Rocksteady liked the mutant name, Bebop didn't. They fought all six of their enemies over the batch of retro-mutagen Donatello had concocted, seeking to become human again. After an ultimately unsuccessful battle with the Turtles, the duo escaped. They were able to recapture Karai and deliver her to their new master. Rocksteady became the Shredder's connection to the Russian mafia, as mentioned in "Casey Jones Vs. the Underworld".

In "The Noxious Avenger," Zeck and Rocksteady were tasked by Stockman to retrieve a chemical known as "Reagent-X" (and some groceries, to their anger) in order for to create a Mind Control Serum for Shredder to use on the Mighty Mutantimals and Karai, inadvertently finding some mutagen in the process. During their battle with the Turtles however, the mutagen they found wound up being thrown by Zeck all over humble sewer worker-turned-garbage man Garson Grunge, who mutated into Muckman. After witnessing him defeat the Turtles in a later encounter, Bebop and Rocksteady took advantage of the lost and confused Muckman, by convincing him that it was the Turtles' doing for his mutation. Muckman then temporarily helped the duo steal the Reagent-X fighting the Turtles, but eventually came to his senses after noticing Bebop and Rocksteady's true nature when the Turtles rescued him, thus turning on them and destroying the chemical, which caused Bebop and Rocksteady to retreat. In "Meet Mondo Gecko," the two attended Xever's underground mutant race with the rest of the Foot and other mutants who were foes of the Turtles. In "The Deadly Venom," a mind-controlled Karai was able to defeat Rocksteady in combat as part of a test to see if the mind-control serum worked on her.

Rocksteady and Bebop were featured in the following TMNT Adventures series, with similar origins and dimwittedness. Like the cartoon, they were street gang members mutated by the Shredder to help him defeat the turtles.

As the series progressed, the animal side of Bebop and Rocksteady surfaced as they dreamed and longed for the 'old days' when they were just animals in the wild (Rocksteady in particular had dreams where he was a real rhino in the wild). When the Shredder and his bunch were defeated by the TMNT in the 'Final Conflict' (issue #13), Rocksteady and Bebop were banished to an Eden World, a huge paradise planet in Dimension X full of wilderness and natural wildlife, without any humans or similar to disrupt their peace, and they enjoyed it.

In issues #23-#25, Krang, who was banished to the toxic waste dump planet Morbus for exiled criminals, befriended two other criminals, Slash and Bellybomb. The group stole a spaceship and headed to Earth and happened to stop along the way at the same Eden World Bebop and Rocksteady inhabited. Being bored of Paradise, Rocksteady and Bebop join them on the trip back to Earth. However, rather than battle the turtles, the pair left Krang and the villains to fight the turtles and wandered the streets of New York City on their own. They rob a clothing store to get clothes similar to their original attire. They then rob a gun store for some guns. Then they went to the zoo and blasted all the cages, setting all the animals free. Just as the turtles managed to defeat Krang (who had taken over Shredder's body), Rocksteady and Bebop arrived with guns and all the zoo animals, intending to take them back to the same Eden World. The turtles surrendered and let Bebop and Rocksteady escape in the spaceship with the animals. Leonardo asked them to take the defeated Krang and Bellybomb with them back to Morbus in Dimension X (Slash had already left the scene and was wandering the city). Bebop and Rocksteady did as asked and bid the Ninja Turtles farewell. The final panel of #25 shows the two mutants removing their clothes and going back to their simple life in the wilds of the Eden World.

Bebop and Rocksteady maintained the abilities they demonstrated in the cartoon, including their superhuman strength. After the initial mini series, the duo seems to have gotten even dumber than their cartoon versions.

Bebop and Rocksteady are shown in their human forms in the Raphael Micro-Series One-shot. They work alongside an Arctic fox mutant named Alopex and appear mutated in issue 25. Their back story is told in issue 7 of the TMNT Villain Micro-Series that was released on October 30, 2013.

In this version, they fully understood the implications of their mutation, having successfully fought and defeated all other candidates for the right after being defeated by the turtles as humans. It is revealed in the micro-series that having been kicked out of gangs in the past owing to their incompetence, they are fanatically determined to remain in the Foot Clan.[12]

They were ordered by Shredder to kill Donatello which they carried out. Donatello fought alongside Metalhead, however, Metalhead was damaged and Donnies Bo Staff was broken by Bebop. Rocksteady smashed Donatello's shell which left the lifeless turtle in a pool of blood. Luckily, they didn't kill off the brain turtle. He was still alive and was in Metalhead while his turtle body was being restored to how it was thanks to Rocksteady.

In the 1987 cartoon series, Rocksteady and Bebop were armed with various types, makes, and models of firearms and laser weaponry from both Earth and Dimension X. In the early episodes of the 1987 cartoon series, Bebop and Rocksteady were armed with automatic rifles and machine guns, which they used against the Turtles. Later in the series, they were armed with laser rifles and pistols from Dimension X. In "The Cat Woman from Channel Six", Rocksteady carried a sword and Bebop carried a baseball bat.

Besides the extensive array of firepower from both Earth and Dimension X at their disposal, Bebop and Rocksteady were also armed with combat knives; Bebop with a double-edged knife (which resembles the Fairbairn-Sykes Fighting Knife) and Rocksteady with a Bowie knife. In some episodes, they are seen fighting over a club.

The use of firearms and laser weaponry by Bebop and Rocksteady help to differentiate them from both the Teenage Mutant Ninja Turtles, Splinter, the Shredder, and the Foot Soldiers/Ninjas who use traditional ninja weaponry. This is because Bebop and Rocksteady were never ninjas, but street punks that were skilled in the use of firearms and knives before they were mutated.

In the game series they use a variety of different weapons. In TMNT: The Arcade Game, Rocksteady used a machine gun while Bebop used a ray gun. In The Manhattan Project, Rocksteady uses a harpoon gun, while Bebop uses a ball and chain mounted on his head. In Turtles in Time, Rocksteady and Bebop were dressed as a pirate captain and first mate respectively. Rocksteady used a rapier while Bebop used a whip.

In the 2012 series, Anton Zeck/Bebop is equipped with many gadgets, such as z-ray glasses, a sliding backpack, a tub of glue, a cloaking device run by Double A batteries, a laser Mohawk, and laser belt. Ivan Steranko/Rocksteady is equipped with a golden hammer and sickle (which he started using in "The Noxious Avenger") as well as and various guns (mini, tranquilizer, etc.).

In the 2003 series episode "Fallen Angel", two characters are seen that are dressed like Bebop and Rocksteady, and resemble their pre-mutated appearances. In the episode "Samurai Tourist", the character Gen, also an anthropomorphic rhinoceros, puts on human clothing that makes him look almost identical to Rocksteady. Also in that episode, Gen is chased by Kojima, an assassin who happens to be a humanoid warthog.

In the Fast Forward episode "Future Shellshock", Michelangelo falls out of a flying truck and onto another vehicle, the driver of which greatly resembles Bebop, only with smaller, more modern sunglasses.

The 2007 film TMNT features the song "Shell Shock" by Gym Class Heroes during the end credits. Bebop and Rocksteady are mentioned in the song.

Bebop and Rocksteady both appear in the 25th Anniversary crossover movie, Turtles Forever, voiced by Braford Cameron (Bebop) and Johnny Castro (Rocksteady). Their human forms are also seen when the Turtles first travel back to the 1987 dimension.

Rocksteady and Bebop both appear frequently in the classic TMNTvideo games, which are based on the 1987 cartoon. They are usually level bosses, usually for one of the levels of the first half of the game—meaning they are easily defeated. Their exact placements vary from game to game:

In the original TMNT arcade game, the Turtles defeat Rocksteady in the first level and Bebop in the second level, and then have a rematch with Rocksteady and Bebop together immediately before rescuing April. Occasionally, Rocksteady and Bebop will bump into each other in their attempts to charge the Turtles, but it does not affect their energy. When the game was released on the NES, the rematch with Rocksteady and Bebop was replaced with a second battle with Baxter Stockman in his mutated insect form.

Rocksteady and Bebop are not part of the original arcade version of Teenage Mutant Ninja Turtles: Turtles in Time. However, they are part of the Super NES port of the game. They are paired together as a double-boss, and appear in the pirate ship level Skull and Crossbones where the time travel goes to 1530, which in the arcade version was formerly Tokka and Rahzar's level (Tokka and Rahzar became mini-bosses in the Technodrome level instead). As in the arcade game, they can bump into each other in their attempts to charge the Turtles; however, they do take damage for it this time. In fact, the player only needs to attack one of them in order to defeat both. As appropriate for the level, they are both dressed in pirate regalia instead of their usual attire, and wield a whip and a rapier instead of firearms.

Bebop and Rocksteady were among the first 10 action figures released by Playmates Toys in 1988. Rocksteady was packaged with a "Retromutagen Rifle" which was most likely modeled after a US ArmyM60 general purpose machine gun. Other accessories included a "Turtle Carver Knife" (a bowie knife), a "Manhole Cover Shield", and a removable belt with turtle shell trophies. Bebop was packaged with a "Turtle Shell Drill" (which resembled a power drill but with its own telescopic sight attached), a double-edged knife that resembled the Fairbairn-Sykes fighting knife, and a trashcan lid for a shield. Both retailed originally at $3.98 each.

Bebop and Rocksteady saw continuous release as they were on store shelves for close to a decade from 1988-1995. Three years later both Bebop and Rocksteady were reissued as KB Toys exclusives commemorating 10 years of the first toy line. It should be noted that the reissues have the date stamps changed from 1988 to 1998. Both figures were reissued again in 2009 to commemorate the 25th anniversary of Teenage Mutant Ninja Turtles franchise. Other figure incarnations of Bebop and Rocksteady were produced for the Wacky Action, Night Ninjas, Mutant Military 2, Mutation, Smash 'em/Bash 'em, Tournament Fighters, Sewer Heroes, and Warriors of the Forgotten Sewer sub lines and in 13 in. "Giant" scale. In Late 2013 Classic Collection Figures of Bebop & Rocksteady Will Be Released.